I do like Joann's for notions, yarn, needles etc. I went yesterday with two coupons and got some great stuff including two squeeze balls things for when my hands get stiff from knitting etc. I don't usually buy fabric there but do buy interfacing - especially when it's on sale.
Ours is expanding over the summer. I've been to some of the big stores in Florida - wow.
Having said all of that, I do agree with the poster that said if you can find what you need without Joann's, you shouldn't worry about what you are missing.
I think the site can be confusing. My store is convenient - drive by it on my way to and from work. I usually do projects with my schoolkids and it's a great place to find that stuff and I get a small educator's discount.
:)